.\" Copyright (c) 2011 Kai Wang
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.\" $Id: dwarf_add_AT_dataref.3 3961 2022-03-12 15:13:22Z jkoshy $
.\"
.Dd September 4, 2011
.Dt DWARF_ADD_AT_DATAREF 3
.Os
.Sh NAME
.Nm dwarf_add_AT_dataref
.Nd create an attribute descriptor for a relocatable address
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft "Dwarf_P_Attribute"
.Fo dwarf_add_AT_dataref
.Fa "Dwarf_P_Debug dbg"
.Fa "Dwarf_P_Die die"
.Fa "Dwarf_Half attr"
.Fa "Dwarf_Unsigned pc_value"
.Fa "Dwarf_Unsigned sym_index"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_add_AT_dataref
creates an attribute descriptor for a relocatable address and attaches
it to the debugging information entry referenced by argument
.Fa die .
.Pp
If flag
.Dv DW_DLC_SIZE_64
is set, the address value will be 8 bytes in size and of the DWARF form
.Dv DW_FORM_data8 .
Otherwise, the address value will be 4 bytes in size and of the DWARF form
.Dv DW_FORM_data4 .
.Pp
Argument
.Fa dbg
should reference a DWARF producer instance allocated using
.Xr dwarf_producer_init 3
or
.Xr dwarf_producer_init_b 3 .
.Pp
Argument
.Fa die
should reference a debugging information entry allocated using
.Xr dwarf_new_die 3 .
.Pp
Argument
.Fa attr
specifies the attribute code of the created attribute descriptor.
.Pp
Argument
.Fa pc_value
specifies the value of the relocatable address.
.Pp
Argument
.Fa sym_index
specifies the ELF symbol index of the symbol to be used for
relocation.
.Pp
If argument
.Fa err
is not
.Dv NULL ,
it will be used to store error information in case
of an error.
.Sh RETURN VALUES
On success, function
.Fn dwarf_add_AT_dataref
returns the created attribute descriptor.
In case of an error, function
.Fn dwarf_add_AT_dataref
returns
.Dv DW_DLV_BADADDR
and sets the argument
.Fa err .
.Sh ERRORS
Function
.Fn dwarf_add_AT_dataref
can fail with:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
Either of the arguments
.Fa dbg
or
.Fa die
was
.Dv NULL .
.It Bq Er DW_DLE_MEMORY
An out of memory condition was encountered during the execution of the
function.
.El
.Sh SEE ALSO
.Xr dwarf 3 ,
.Xr dwarf_add_AT_ref_address 3 ,
.Xr dwarf_add_AT_reference 3 ,
.Xr dwarf_add_AT_signed_const 3 ,
.Xr dwarf_add_AT_unsigned_const 3 ,
.Xr dwarf_new_die 3 ,
.Xr dwarf_producer_init 3 ,
.Xr dwarf_producer_init_b 3
